Discount & sales tax
Stack two discounts, add a tax rate, and see the final price and actual saving.
Everyday moneyEveryday money
Unit price showdown calculator
Which bag is the better neigh-gain?
Your numbers
Compare two packs fairly—even when their sizes are different.
TRY AN EXAMPLE
Your answer is just a moment away.
Enable JavaScript to calculate. The formulas and examples below work without it.
Saved scenarios stay in this browser. No account, no upload.
THE MATH, WITHOUT THE MYSTERY
What’s actually happening here?
A bigger pack is not automatically better value. Dividing each price by its quantity puts both options on the same footing.
Use exactly the same unit for both quantities. For 500 grams versus 1 kilogram, enter 500 and 1,000—not 500 and 1. The saving percentage compares the cheaper unit price with the more expensive one.
THE FORMULA
Comparable price = Pack price / Pack quantity × Comparison quantity
A small example
A 500 g pack at 4.50 costs 0.90 per 100 g. A 1,000 g pack at 7 costs 0.70 per 100 g. Pack B is about 22.22% cheaper per unit.
GOOD QUESTIONS
A few things worth knowing.
Can I compare liquids or multipacks?
Yes. Use milliliters for both liquids, or piece counts for both multipacks. Do not mix units.
What if both have the same unit price?
The tool calls it a tie. A smaller pack may still be preferable if it avoids waste or reduces the amount spent today.